1. Technical Field of the Invention
This invention relates to hot air blower-type track switch snow melters, and more particularly to a connection system for connecting track switch snow melter ducts for use in blower-type track switch snow melters.
2. Description of the Prior Art
Hot air blower-type track switch snow melters have become standard equipment for railroads operating in cold climates. For those railroads, snow and ice build-up at track switches is a problem and track switch snow melters have become the solution of choice. With track switch snow melters, rather than laboriously clearing switches of snow by hand, the task can be done automatically.
Track switch snow melters generally have a plurality of snow sensors that detect the presence of snow in switching areas. These sensors relay a signal to a control panel on a heat source or blower unit. When snow is detected, hot air is blown through a system of ducts which direct a stream of hot air through various nozzles and outlets to critical areas of the switch which must be kept free of snow and ice.
The placement of the ductwork is a difficult and critical aspect of the installation of hot air blowers. The ducts must be both proximate to the rails so that the hot air can melt the snow and ice around them and at the same time not obstruct passing trains. One arrangement that has been used to accomplish these dual objectives is to place a first duct running from the heat source parallel to and between two ties and beneath the rails of the track. From the first duct, low profile nozzles are extended to direct hot air at critical parts of the switching mechanism. In addition to the nozzles, additional ducts are extended from the first duct perpendicular to the ties and parallel to the rails. These ducts are attached to the top of the ties by straps that extend over the ducts and that are bolted to the ties. Openings along the side of these ducts direct hot air to areas to be kept clear of snow and ice.
Although track switch snow melters have been an important labor-saving device for keeping track switches clear of snow and ice, the ductwork must be removed whenever the track is to be routinely maintained. Unfortunately, with currently-used configurations of the ductwork, this is a time-consuming process. In particular, the first duct must be pulled out from between the ties in a single segment. Considerable effort is required to slide the first duct out because the first duct is approximately as long as the ties, making it very cumbersome. In addition, friction is created between the sides of the first duct and the ballast. Moreover, flanges protruding from the first duct can engage the ballast, adding to the difficulty of removing the first duct.
Therefore, there arises a need for a track switch snow melter which has ducts which can be easily connected and disconnected to allow for the easy removal of the duct segments during track maintenance.